Hard scale or asphaltenes can create challenges for well intervention operations, which may be aided by spotting chemical solvents, acid, etc. Other operations such as well abandonment may require spotting cement. For all these operations, dump bailers are the standard solution. However, their effectiveness in dumping cement, or other fluid, to a target depth is inconsistent.

Dispensing fluids with confirmation at a target depth without premature release or contamination of the dispensing fluid is an operational challenge.